Airtel — complaining about my 4g data service

Address:

Abhayapuri ward no.3 pachduar PO Abhayapuri Dist Bongaigaon State Assam, Bongaigaon, Assam, 783384

I have been using airtel since last 5 months.1st there has no issue about the internet after that from last 5 days i'm facing vary much problems of internet connectivity and volte service. The call can't be completed and data service is so poor that even i can't check any of my internet services. I complaint airtel customer care from last 3 days. But they have just assured me but don't take any actions about my complaint. Airtel 558 data plan is activated in my sim. Which has 3 gb data/day and all national calling is free and 100 sms/day for 82 days.